Author Topic: Nearly a tank-slapper!  (Read 7581 times)

0 Members and 1 Guest are viewing this topic.

Offline WillyP

  • I Need a Life
  • ******
  • Posts: 6133
  • Live Free Or Die
    • Suncook Carpentry
  • AREA: Northeast Area
  • COG#: 8799
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #25 on: July 26, 2011, 02:45:23 am »
If it swings side to side smoothly the bearings are probably ok.
Smart people look like crazy people to stupid people.
pics

Offline JPavlis_CA

  • San Jose CA
  • Sport Tourer
  • *****
  • Posts: 2262
  • AREA: Southwest Area
  • COG#: 2293
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #26 on: July 26, 2011, 03:15:34 am »
Jenn - think about what you did....  removed the wheel, popped the fork caps to check the oil, changed handlebars. The problem started after you did this. At no time did you mess with the bearings until after the problem started, right?

Focus on what you did, even if it means going back through each step again.
All God's male children tend to be low-life, sleaze-ball, early apexers - Terry Earwood, Chief Instructor, Skip Barber Racing School.

Offline coffee_brake

  • Crotch Rocket
  • ****
  • Posts: 1573
  • AREA: Southeast Area
  • COG#: 7653
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #27 on: July 26, 2011, 03:30:18 am »
Well, and I also changed a tire.

That's one of the things I did, that I changed tonight. It seems to have helped.

I only messed with the bearings because I was mistaken in the level of "swing" I thought was right at the bars. Now I think the sloppy bearings may have caused the cupping in the first place.

Willy the movement is smooth, no notching. Maybe it's OK.

The little shimmy at 45 is really strange, it fixes itself with my hands off the bars. It is a very tiny shimmy, I was looking hard to find it.
I'll take it on some faster roads tomorrow.

The only thing left is to pull the whole thing back off and check the fork oil again--and I knew when I did it that I didn't want to do it again, and I was really, really careful to get them the same with the Moition Pro tool, the one that can remove the last little bit of excess oil.
Jenn in "Chaahlston, y'all...."

Offline JPavlis_CA

  • San Jose CA
  • Sport Tourer
  • *****
  • Posts: 2262
  • AREA: Southwest Area
  • COG#: 2293
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #28 on: July 26, 2011, 04:21:40 am »
Jenn - whenever I have a shopping cart castor type shimmy, my first thought is to check the rear tire pressure, and shock pressure if still using the OEM air shock. If either is low, you can get a wobble. I learned this on my 87 Venture which was a real pain to check rear tire pressure and the shock slowly lost air, so I'd just wait till I got the hands off 40mph decel wobble to check it.

Fork oil level wouldn't be the problem, you'd feel that in how the front end responds to bumps. It would have no affect on the wobble.

What's this 15 lbs on the adjuster you mention? Get a fish scale and do it right. Doing it by flopping the bars with a nudge is not the right way to do it. I've seen steering stem nuts that were cranked way too tight and the bars still flopped with a nudge. Remember, roller bearings do not like axial loads, but unfortunately, the Connie requires just a bit of axial load to prevent head shake. Torque the nut down tight, back off till just loose, and then retighten 1/8 to 1/4 turn. Done.
All God's male children tend to be low-life, sleaze-ball, early apexers - Terry Earwood, Chief Instructor, Skip Barber Racing School.

Offline coffee_brake

  • Crotch Rocket
  • ****
  • Posts: 1573
  • AREA: Southeast Area
  • COG#: 7653
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #29 on: July 26, 2011, 09:15:06 am »
Fish scale?

Huh, never heard of that.
If a torque wrench measures the force on the bolt at the head of that bolt..i.e. at the very point of the part-to-part friction, then how would you measure if you had the measuring tool an inch or more away from the force, like on the handle of the neck adjuster spanner?

How are the rest of you folks measuring this? Everybody has a fish scale in the garage?
Along these lines, couldn't I push on the handle of the wrench with a good old bathroom scale to get a measure?
Jenn in "Chaahlston, y'all...."

Offline conando

  • Mini Bike
  • **
  • Posts: 116
  • AREA: Northeast Area
  • COG#: 7631
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #30 on: July 26, 2011, 11:14:26 am »
Regardless of the torque you apply with the steering nut adjuster wrench, the bars must swing freely with minimal resistance. It' similar to, but on a smaller scale as when you adjust the valve clearances, pulling the feeler gauge out with slight resistance will give the gap shown on the feeler gauge. You don't need a torque wrench.

The bearings should be alright, if when properly adjusted you feel no notching or grittiness throughout the full range of the steering arc. The resistance should also be even throughout that range without loose or tight spots.

Yes, loose steering bearings contribute to early cupping of tires. Once a tire is badly cupped, there is no way you can't get a decel wobble. Don't expect any better until you put a brand new tire on.  Tires last longer before getting cupped when the steering bearing is properly adjusted. Tires will barely cup during their lifetime when all things affecting the handling of the bike are properly adjusted, although some tire brands are more prone to cupping than others.
COG#7631  2000 Concours-sold, 2008 FJR1300, 1974 Norton Commando Roadster

Offline Bob_C_CT

  • Sport Tourer
  • *****
  • Posts: 2222
  • AREA: Northeast Area
  • COG#: 9544
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #31 on: July 26, 2011, 12:03:26 pm »
I think he is talking about measuring the force in Lbs with the fish scale on the handle bar ends to see how much it takes to move the handle bars from stop to stop. I don't know what that reading would be, pretty low I would think, JMHO.

Stupid question because you seem to have experience wrenching but I have to ask, you are loosening either the top or bottom triple tree pinch bolts before adjusting the steering head and re tightening after.   

I did mine by feel just a slight nudge to push bars from center to stops without any notchy feel and not so loose that they fall to stop and bounce back off of stop. Don't go too tight or the bike will try to steer itself, weird feeling.
Note: When you tighten the steering head locking nut it will tighten the steering slightly more.

May want to recheck fit of fork brace after you are happy with steering head adjustment or remove prior to any adjustment to rule out that fork sticktion is the problem.


Southern Connecticut.
97 C10,ZRX Front, Meanstreak rim

Offline JPavlis_CA

  • San Jose CA
  • Sport Tourer
  • *****
  • Posts: 2262
  • AREA: Southwest Area
  • COG#: 2293
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #32 on: July 26, 2011, 12:38:37 pm »
There's calculations for force when the axis of the measuring instrument isn't in direct line with the bolt/nut, but that isn't necessary here.

I fish scale (for weighing fish, and yes, lots of people have them, I I use mine to get the proper track tension on my snowmobile) would be attached to the end of the handlebar and the amount of pull measured to turn the bars front dead center - about 1 lb.

But really, with the steering crown, it's all about feel. Just don't axial load roller bearings, they don't like it. As Bob said, too tight and the bike won't self center and you will be constantly fighting the steering to go straight. Which is why the proper way is to tighten them down to seat the bearings, back off till just loose, and then tighten just a bit.
All God's male children tend to be low-life, sleaze-ball, early apexers - Terry Earwood, Chief Instructor, Skip Barber Racing School.

Offline coffee_brake

  • Crotch Rocket
  • ****
  • Posts: 1573
  • AREA: Southeast Area
  • COG#: 7653
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #33 on: July 26, 2011, 02:17:39 pm »
OK thanks for everyone's input. The more ways people say it, the better I'm understanding it.

I think my bearings have always been too loose, that's why every front tire I ever installed on the Concours cupped badly, this last one worse than all the rest. Of course I was under the impression that the fork was supposed to bounce off the stops. Now I see that's way too sloppy. And I do understand about too tight, I think. Yesterday I made it so tight that it took a good shove at the fener (bars are off) to move the tire. As much pressure as you would use to open the legs on a folding table. Then I backed off from that to the point that just a little nudge would move the forks, maybe the same pressure as you need to open the latch on the saddlebags. Sorry for the weird terminology, haven't found a fish scale yet... ;D

Now I see what I was doing wrong, and I have a fresh new tire.
Today I'm yanking the fork brace and also re-checking tire pressure and rear shock pressure (I already checked the swingarm and wheel bearings, all good). Then I'm going down a good fast road where I can check it out safely at all speeds and make sure it neither oscillates or fights my input.

And yes, as I understand it, it is impossible to adjust the steering stem bearings without removing the top triple, so it's completely off the tubes when I turn the adjuster nut.

Googling "axial load," I don't see how the bearings can avoid it when adjusted. There has to be SOME axial load on them, right?

Jenn in "Chaahlston, y'all...."

Offline Bergmen

  • Sport Tourer
  • *****
  • Posts: 2390
  • AREA: Southwest Area
  • COG#: Forum
  • Membership Level: Forum Subscriber
Re: Nearly a tank-slapper!
« Reply #34 on: July 26, 2011, 04:01:32 pm »
Okay, I'll weigh in here with some thoughts even though there is quite a bit of excellent information here from those in-the-know.

I'm no bearing expert but I have applied rolling element bearings in my work at times. First of all, the steering bearings in motorcycles are used in a static or near static load condition. That means they are subjected to shock loads in stationary positions repeatedly (driving straight ahead over bumps). The tapered roller bearings that the Concours (and many motorcycles) use has excellent radial and axial load bearing capabilities, the frustrating part of the application is the stationary (or static) state of the bearings during these loads. This is what worries the bearing companies and there are extensive treatises on this (as well as all other bearing application design notes) at many bearing manufacturers websites. Here is a link to SKF (a leading bearing manufacturer):

http://www.skf.com/portal/skf/home/products?maincatalogue=1&lang=en&newlink=1_0_1  This gets a little geeky at times but it still is a good read.

Proper lubrication and adjustment of these bearings (in this application especially) are crucial to minimizing damage and assuring long life. Nothing new here. The difficulty is determining proper adjustment (lubrication is not nearly as mysterious).

I'll boil things down to the essentials here. In my long experience with steering bearings I have found that the proper adjustment is when the bearings are as tight as possible without adversely affecting straight line stability, just like Jim P stated above. When I picked up my new 1979 Yamaha XS-1100 and I rode the bike home from the dealers the bearings were way too tight and I couldn't hold a straight line. Motorcycles that were imported at that time had to be delivered with the front ends disassembled (import restrictions) and they were finally assembled at the point of entry. The gorilla who put mine together over did it. Luckily they weren't damaged.

With the Concours, this can be achieved by adjusting the bearings with the front end off the ground until there is noticeable drag from lock-to-lock. Spring scales can be used to measure this but I prefer to "feel" this with my own hands. Once you tighten the lock nut it will increase the preload and the lock-to-lock drag so some fine tuning is required here. Take it slow and methodical and you will see what I mean here. This will take an inordinate amount of torque on the pin spanner to achieve this, it will feel like you are way over-tightening the bearings. This is normal, just proceed to the point I describe above. If it takes a road test to feel an over-tightened bearing, that's okay, you will know to back off just a little and you will have it.

Hope this helps.

Dan
--2014 Yamaha FJR1300A--
--ZGRX 1200 Concours (sold)--
--SPOOFAK Inventor--

Offline coffee_brake

  • Crotch Rocket
  • ****
  • Posts: 1573
  • AREA: Southeast Area
  • COG#: 7653
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #35 on: July 26, 2011, 04:07:44 pm »
Three test rides later, I am much happier but no less baffled.

My test route goes up to 55 and included three gentle hills and some places to accelerate while leaned over. Also a huge empty parking lot to push it a bit at parking lot speeds.

First of all, I yanked the fork brace and front fender. Added a little air to the rear shock, tire was fine. Rode it. Got ZERO headshake.

Then I put the fork brace and fender back on, and got a headshake ONLY on the hills, and only at 45 mph. I could not replicate it on level ground by leaning forward over the tank, and I could not replicate it by sitting on the passenger seat with my feet on the passenger pegs. I figured it was either the brace or the fender, and whichever I removed, the next ride would show the culprit.

But I made a mistake, when I went to remove the fork brace, I found one bolt that had loosened up as I torqued the others. I took it loose, torqued and re-torqued it to be sure, and took it out. No headshake on the third ride.

Mind you, it's a heckuva miserable hot humid day to run circles in town in traffic chasing some ever-decreasing occurance of headshake, I'm done for a while. I'd like to try again this afternoon when it feels fresh to me again.

I didn't like the handling without the fork brace at all, I'm spoiled to it. It really does fit properly I think. The main piece sits in the grooves on the forks without the end pieces even installed. The paint rubs but I don't have to use any strength to put it in position.

What kind of bar ends do I use? These bars are Ebay, I gave my set away like an idiot years ago, thinking I'd never want it. But now it feels right again. Except the bar ends are missing and I think the weight on there would help.

I'm still listening, I've gotten it riding OK but this afternoon I'll try a different route and see if I can make it do the headshake again. I'm hoping this problem is about over....
Jenn in "Chaahlston, y'all...."

Offline coffee_brake

  • Crotch Rocket
  • ****
  • Posts: 1573
  • AREA: Southeast Area
  • COG#: 7653
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #36 on: July 26, 2011, 04:17:32 pm »
Dan, that's exactly what I thought, I thought I was damaging either the bearings or the disc-washer under that nut. I thought I was going to ruin the nut or the tool, I was twisting so hard. I had a pipe on the end of it to turn it, I needed extra leverage. Then I backed off a bit. I was telling myself I was crazy to damage the motorcycle like this and ruin the wrench too, but that's how much force it was taking to reach the place called "hard to turn" ya'll are describing.

Yes, that helps, that and the bit on tapered bearings. Thanks a lot. A whole lot.
Jenn in "Chaahlston, y'all...."

Offline Rev Ryder

  • Officer
  • I Need a Life
  • ****
  • Posts: 8809
  • We came. We saw. We Concours-ed.
    • Presbychuck
  • AREA: South Central Area
  • COG#: 7235
  • Membership Level: Executive Director
Re: Nearly a tank-slapper!
« Reply #37 on: July 26, 2011, 04:28:41 pm »
Miss Jenn,
You are freaking me out.  You have absolutely the MOST trouble with your Connie... I'd shoot it if it treated me like that.

I hope that you are on the verge of getting it sorted.  My first thought certainly would have been the tire (not properly seated, bad belt, on reverse rotation, etc), of course if it was good when removed you'd naturally expect it to function the same all things being equal. 
Fortis non Ferox
 Shafties Can't Wheelie

Offline Ranger Jim

  • Iron Butt
  • *****
  • Posts: 3575
  • AREA: Southeast Area
  • COG#: 6720
  • Membership Level: Asst. Area Director
Re: Nearly a tank-slapper!
« Reply #38 on: July 26, 2011, 04:41:40 pm »
I've got some barends you can have. I'll have to look for them.  I THINK I have both a set of stock and a set of Stainless Steel Manic Salamander.
JIM CULP
OtP Jr. Slave Laborer (Safety)

If you can't be a good example; be a WARNING!

Offline coffee_brake

  • Crotch Rocket
  • ****
  • Posts: 1573
  • AREA: Southeast Area
  • COG#: 7653
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #39 on: July 26, 2011, 05:11:15 pm »
Bike's just doing what bikes do at 60k miles I guess: need stuff done. And I don't know enough about it to do the stuff without either screwing it up and having to ask for help...or maybe just ask for help to begin with! I thought I knew what to do.
The bike's always brought me home Rev...except that one time the fuel line collapsed at night and the bike was only a year old and I couldn't figure out why there was no fuel...but other than that it's always brought me home!

Jim's already given me lots of stuff for the Connie, I wasn't asking to be given parts, I was just asking if there's a common name for the kind of bar ends that will fit. Looks like most of the 90's ZX and Ninja ones on Ebay will fit....hey I might go for fake chrome, really classy! Looks like the same thread size, anyway....
Jenn in "Chaahlston, y'all...."

Offline Bergmen

  • Sport Tourer
  • *****
  • Posts: 2390
  • AREA: Southwest Area
  • COG#: Forum
  • Membership Level: Forum Subscriber
Re: Nearly a tank-slapper!
« Reply #40 on: July 26, 2011, 05:25:04 pm »
Bike's just doing what bikes do at 60k miles I guess: need stuff done. And I don't know enough about it to do the stuff without either screwing it up and having to ask for help...or maybe just ask for help to begin with! I thought I knew what to do.
The bike's always brought me home Rev...except that one time the fuel line collapsed at night and the bike was only a year old and I couldn't figure out why there was no fuel...but other than that it's always brought me home!

Jim's already given me lots of stuff for the Connie, I wasn't asking to be given parts, I was just asking if there's a common name for the kind of bar ends that will fit. Looks like most of the 90's ZX and Ninja ones on Ebay will fit....hey I might go for fake chrome, really classy! Looks like the same thread size, anyway....

If you have tubular bars, you probably won't have the bar end nuts welded into the ends like the stock bars have (to mount the end weights). I have a simple method that has worked on my tubular bars. Let me know and I can show you what I did.

Dan
--2014 Yamaha FJR1300A--
--ZGRX 1200 Concours (sold)--
--SPOOFAK Inventor--

Offline coffee_brake

  • Crotch Rocket
  • ****
  • Posts: 1573
  • AREA: Southeast Area
  • COG#: 7653
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #41 on: July 26, 2011, 06:22:25 pm »
I'll take you up on that for a project, but I just re-installed stocker bars that have the threads welded in them. This after removing the Goldwing bars that were on there all this time. I can't believe how much I used to hate the stock riding position, I remember swearing to sell my new Concours because I hated the way it felt. Now nothing feels more natural than the slightly forward lean. Weird how things change.

I did just pick up a rotten old CX500 for just about free...and it runs...but will need bar ends of some kind as well. I'd like to hear how you do the bar ends for tubular bars.
Jenn in "Chaahlston, y'all...."

Offline Bergmen

  • Sport Tourer
  • *****
  • Posts: 2390
  • AREA: Southwest Area
  • COG#: Forum
  • Membership Level: Forum Subscriber
Re: Nearly a tank-slapper!
« Reply #42 on: July 26, 2011, 06:22:48 pm »
Miss Jenn,
You are freaking me out.  You have absolutely the MOST trouble with your Connie...I'd shoot it if it treated me like that.

I hope that you are on the verge of getting it sorted.  My first thought certainly would have been the tire (not properly seated, bad belt, on reverse rotation, etc), of course if it was good when removed you'd naturally expect it to function the same all things being equal.

The only right way to do this Chuck is with an incendiary bazooka and a full tank of gas. Video is essential but I shouldn't have to mention that.

But Jenn is on top of things and all will work out well...

Dan
--2014 Yamaha FJR1300A--
--ZGRX 1200 Concours (sold)--
--SPOOFAK Inventor--

Offline Bergmen

  • Sport Tourer
  • *****
  • Posts: 2390
  • AREA: Southwest Area
  • COG#: Forum
  • Membership Level: Forum Subscriber
Re: Nearly a tank-slapper!
« Reply #43 on: July 26, 2011, 09:16:14 pm »
I'll take you up on that for a project, but I just re-installed stocker bars that have the threads welded in them. This after removing the Goldwing bars that were on there all this time. I can't believe how much I used to hate the stock riding position, I remember swearing to sell my new Concours because I hated the way it felt. Now nothing feels more natural than the slightly forward lean. Weird how things change.

I did just pick up a rotten old CX500 for just about free...and it runs...but will need bar ends of some kind as well. I'd like to hear how you do the bar ends for tubular bars.


Okay, here is the method I would recommend. Measure the inside diameter of the bars you want to mount the bar end weights to. Then head to your local hardware store and find a size of "wellnut" that will just fit inside your handlebars:



"Wellnuts" are flanged rubber moldings with a threaded brass insert on one end. You will need a pair of these for each end (four in all). I would get a couple of spares just in case there is any damage while modifying these for installation. In my case, they had a 5/16-18 thread. To mount the bar ends, you will need 5/16-18 stainless socket head cap screws (Allen heads). Length will be determined later.

What I did was take one wellnut and grind the rubber flange off so it is the same diameter as the barrel of the wellnut. With the other wellnut, leave the flange in place but drill out the threads with a drill size that will allow the mounting bolt to slip through (threads not needed on this one), in my case slightly larger than 5/16 inch.

Now the idea is to have the wellnut with the flange removed placed into the bar a couple of inches. In my case, I glued it in place but this is hokey. It worked okay but I hid the ugliness of it. What I would recommend is to make a spacer out of wood or even copper tubing or something. Anything that is smaller in OD than the inside of the handlebars and can be drilled to accept the bolt or has an inside diameter to do the same. This spacer does not need to be longer than 2 inches.

You can determine the length of the bolt needed to mount the bar end weight by adding up all of the lengths. No problem in being a little long.

So, the assembly will look like this: First slip the bar end on the bolt, then the drilled out wellnut with the flange, then the spacer, then thread on the well nut with the flange ground off (threaded insert towards the inside of the handlebar). Leave loose and slip the assembly into the bar end and while holding the flange of the well nut against the end of the bar, tighten the bolt to compress the assembly. Mine has worked for years and I have retightened only once during this time.

Let me know if you have any questions.

Dan
« Last Edit: July 26, 2011, 09:39:15 pm by Bergmen »
--2014 Yamaha FJR1300A--
--ZGRX 1200 Concours (sold)--
--SPOOFAK Inventor--

Offline Rev Ryder

  • Officer
  • I Need a Life
  • ****
  • Posts: 8809
  • We came. We saw. We Concours-ed.
    • Presbychuck
  • AREA: South Central Area
  • COG#: 7235
  • Membership Level: Executive Director
Re: Nearly a tank-slapper!
« Reply #44 on: July 26, 2011, 09:16:59 pm »
Miss Jenn,
You are freaking me out.  You have absolutely the MOST trouble with your Connie...I'd shoot it if it treated me like that.

I hope that you are on the verge of getting it sorted.  My first thought certainly would have been the tire (not properly seated, bad belt, on reverse rotation, etc), of course if it was good when removed you'd naturally expect it to function the same all things being equal.

The only right way to do this Chuck is with an incendiary bazooka and a full tank of gas. Video is essential but I shouldn't have to mention that.

But Jenn is on top of things and all will work out well...

Dan

Yeah, like we used to say on www.texasbowhunter.com ... "it's all about the video." LOL Maybe a DUkes of HAzzard type dynamite arrow and a full tank of gas.   :-\

I know Jenn loves her scooter and I am pretty proud mine has ALMOST always brought me home too, but I hate hearing that she's struggling with it like this.  Scary rides really stink!!!  Jenn, if you were closer you and the missus could sit in the house drinkin' iced tea and I'd be happy to try to help fix it... or I could launch that arrow thingy if necessary.  >:D 

Jenn, I admire your willingness to skin knuckles, expand your vocabulary, and break a nail.

Dan, I just admire you cuz you're so durn smart, good lookin', and cuz yer Connie is dirt proof.   ;)

I hope you're winning.

Fortis non Ferox
 Shafties Can't Wheelie

Offline coffee_brake

  • Crotch Rocket
  • ****
  • Posts: 1573
  • AREA: Southeast Area
  • COG#: 7653
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #45 on: July 27, 2011, 10:19:52 am »
Well that's a simple enough method...now I can put some bar ends on, easy.

I really appreciate the help everybody, and the tool offers, and all...Rev, the missus and I would have to be in the garage with iced tea, I couldn't stand by while somebody else worked on my bike. Still, I really need to meet this woman, she must be made of cast iron...
Jenn in "Chaahlston, y'all...."

Offline Rev Ryder

  • Officer
  • I Need a Life
  • ****
  • Posts: 8809
  • We came. We saw. We Concours-ed.
    • Presbychuck
  • AREA: South Central Area
  • COG#: 7235
  • Membership Level: Executive Director
Re: Nearly a tank-slapper!
« Reply #46 on: July 28, 2011, 12:38:40 am »
Well that's a simple enough method...now I can put some bar ends on, easy.

I really appreciate the help everybody, and the tool offers, and all...Rev, the missus and I would have to be in the garage with iced tea, I couldn't stand by while somebody else worked on my bike. Still, I really need to meet this woman, she must be made of cast iron...
Tempered steel. Even I can't break her.   :)
Fortis non Ferox
 Shafties Can't Wheelie

Offline Douglas

  • Street Cruiser
  • ****
  • Posts: 725
  • AREA: Southeast Area
  • COG#: 8649
  • Membership Level: Event Host
Re: Nearly a tank-slapper!
« Reply #47 on: January 17, 2012, 04:50:25 am »
Coffee_brake:
So, what was it?
ASE Certified mechanic.
Former CCS/WERA licensed racer #51.
"Whatever you do in life surround yourself with smart people who'll argue with you" John Wooden
"Political correctness dumbs down our society because idiots come away propagating their beliefs as though they are correct" Douglas Re

Offline coffee_brake

  • Crotch Rocket
  • ****
  • Posts: 1573
  • AREA: Southeast Area
  • COG#: 7653
  • Membership Level: Active
Re: Nearly a tank-slapper!
« Reply #48 on: January 17, 2012, 01:13:33 pm »
They weren't tight enough.

If you go back a page and read Bergman's repsonse #34, especially the last two paragraphs, that's what I did.

Then, I  had to go back to my other old bikes and do the same thing--re-tighten the bearings to far tighter than I thought they should be.

And if it's too tight, you will know right away, the steering will feel unnatural. If it's not too tight or too lose, the front end just fails to shimmy. And if it's too loose, it does shimmy at some speed, and likely on deceleration.

So now with 67,000 miles on my Concours and several thousand of that on the second set of bearings, here's how I suggest to do the job:

First off, carry the tools with you on any long trips for the first thousand miles. No joke. They settle in a LOT.
Just like Bergman said, I tightened that nut under the top triple until the front tire took some force to move back and forth. Think if you were to push, say, a 2-slice toaster slowly across the kitchen counter. Or a can of soup. That's about how much force it should take to push the front tire back and forth, and this is without any cables/hydraulic lines whatsoever pulling or pushing back. Not the kind of force to throw a can of soup, just enough force to push it across the counter slowly.
I bought the right tool to turn that castellated nut. It's worth it, because the screwdriver method just batters the nut out of shape, it takes so many turns.
Once the nut is so tight that you have to push on the tire ever so little to make it move as described above, back off just a bit to compensate for the pressure the nut on top of the triple will exert, and put it all back together.

I no longer believe the forks should bounce off the stops at all. I don't think they should even fall to the stops, at least not on a Connie. I think they should move freely with just a little pressure to the stops with no catching or notching or dragging, and that's the right tight.

As best I can, that's a summary of what was taught to me in this thread, and the bike's riding just fine all these miles since.
Jenn in "Chaahlston, y'all...."

Offline Bergmen

  • Sport Tourer
  • *****
  • Posts: 2390
  • AREA: Southwest Area
  • COG#: Forum
  • Membership Level: Forum Subscriber
Re: Nearly a tank-slapper!
« Reply #49 on: January 17, 2012, 04:14:36 pm »
Okay, editing my personal notes to add..."2-slice toaster", "can of soup"... got it....(nifty analogies by the way).

Jenn, you keep this up and one of these days we'll be asking you for advice on how to fix these things.

Dan
--2014 Yamaha FJR1300A--
--ZGRX 1200 Concours (sold)--
--SPOOFAK Inventor--